This circuit was obtained from Elektor magazine and published in the Encyclopedia of Electronic Circuits Vol 5 of 1995. Transistors are RF types that are still common today.
With this circuit it is possible to select the upper or lower side band on an SSB transmission by...
This is the circuit of the commercial Japanese megaphone of the 60s model DM-218. The circuit uses...
This circuit was obtained from a 1978 English magazine. This circuit can be easily assembled. We...